JP6329941B2 - Method and apparatus for substrate support with multi-zone heating - Google Patents

Description

  Embodiments of the present invention generally relate to methods and apparatus for forming semiconductor devices. More particularly, embodiments of the present invention relate to a method for processing a semiconductor substrate.

In the field of integrated circuit manufacturing and flat panel display manufacturing, multiple deposition and etching processes are successively performed on a substrate in one or more processing chambers of a substrate processing system to form various device design structures. Executed. Etching, physical vapor deposition (PVD), chemical vapor deposition (CVD), chamber cleaning, substrate polishing, conditioning, and other processes are well known in the art, and each process is often performed in a processing chamber. An appropriate method of heating the placed substrate (eg, silicon substrate) is required.
In general, a silicon substrate (eg, a wafer or glass substrate) is transferred onto a substrate support surface of a substrate support assembly (eg, a susceptor) inside the processing chamber. FIG. 1A shows a top view of a substrate support surface of a substrate support assembly 120 in a processing chamber. The substrate support assembly 120 can include a heating pedestal in which a single heating element 112 connected to the input and output ends of the power supply 114 is embedded.

1A shows that the use of a single heating element 112 results in a single heating zone “A” on the substrate support surface of the substrate support assembly 120. However, since a different portion of the substrate may have different heat losses when placed on the substrate support assembly 120, a single heating zone “A” is used to remove the surface of the substrate placed above. When heated, the temperature distribution is often not uniform between the center and the outer edge of the substrate surface. In other words, after the substrate is placed on the surface of the substrate support assembly 120 and the substrate is heated by turning on the power supply 114, the resulting temperature profile of the substrate surface is often not uniform. It has been found that the edge of the substrate surface loses heat more easily than the center and is cooler. This non-uniform temperature within the wafer can be 6-8 degrees Celsius.
FIG. 1B shows a top view of the surface of another prior art substrate support assembly 140. To improve the temperature non-uniformity in the wafer discussed above, the substrate support assembly 140 is embedded in the substrate support assembly 140 and has two heating elements connected to the input and output ends of the two power supplies 114A, 114B, respectively. 112A, 112B can be included. The frame in FIG. 1B shows two heating zones “A” and “B” on the surface of such prior art substrate support assembly 140 when two heating elements 112A, 112B are used. To compensate for heat loss at the outer edge of the surface of the substrate when the substrate is placed on the substrate support surface of such prior art substrate support assembly 140, the heating zone “B” is generally higher from the power source 114B. Use power input.

  However, in order to create multiple temperature heating zones (multi-zones) within such prior art substrate support assembly 140, multiple heating elements (FIG. 1B include two heating zones “A” and “B”). When at least two heating elements to produce are used), these heating elements have multiple power controllers, multiple cables and multiple power supplies (FIG. 1B has at least two power supplies 114A, 114B). Must be combined). Each heating element must be assigned a dedicated at least one power controller and a dedicated at least one power source. Thus, such a multi-zone substrate support assembly 140 design represents an undesirably heavy load on software control and hardware design.

Furthermore, if multiple power sources are used to mechanically adjust the heating temperature output of these heating elements, at least twice (2 ×) more electrical cables and mechanical auxiliary hardware for each power source. Wear is required (eg at least one input line / input end for each power supply and at least one other output line / output end connected to each heating element). These power input lines / input ends and output lines / output ends must all be housed inside the support pedestal (eg shaft) of the substrate support assembly, which makes the pedestal design too bulky and mechanical design Increase the load. Accordingly, there is a need for a substrate support assembly that has a small number of mechanical parts and a simple mechanical design.
Further, the output temperature between the different temperature zones of such a multi-zone substrate support assembly 140 is controlled by a fixed electrical input of a power source (each power source is connected to a respective heating element in each zone) It is often difficult for those output temperatures to adjust all output temperatures after substrate processing has begun. Accordingly, there is a need for a substrate support assembly that has the ability to adjust the heating power over a wide temperature range and multiple heating zones during substrate processing.

  Accordingly, an improved substrate support assembly having a simple heating element design and improved substrate heating efficiency, wherein the surface of the substrate support assembly is adjustable between a plurality of adjustable heating zones within the substrate support assembly of a substrate processing system. There is a need for a substrate support assembly that further has the ability to regulate temperature.

  Methods and systems are provided for controlling the temperature of the surface of a substrate disposed on a substrate support surface of a substrate support assembly of a processing chamber. In one aspect, a minimal heating element design (e.g., a single heating element connected to a single power source that can adjust the surface temperature of the substrate support assembly to create multiple temperature zones that can be temperature adjusted). A substrate support assembly is provided. Using a single heating element, the single heating element is embedded and distributed in the desired pattern inside the substrate support assembly to provide improved substrate heating efficiency and overall substrate support surface. A desired output temperature distribution profile can be obtained.

In one embodiment, a substrate support assembly of a substrate processing chamber includes a support member having a substrate support surface and a heating element having two or more heating element sections. These heating element sections are connected together as one electrical loop, and each heating element section independently responds differently to the input power of the power source connected to the heating element. In other embodiments, the heating element is provided for heating two or more heating zones of the substrate support surface, wherein each heating element section of the heating element includes a respective heating zone of the substrate support surface of the support member. Independently configured to heat.
In another aspect, the substrate processing chamber includes a substrate support assembly disposed inside the substrate processing chamber, the substrate support assembly having a support member having a substrate support surface and two or more heating element sections. Elements. These heating element sections are connected together as one electrical loop, and each heating element section independently responds differently to the input power of the power source connected to the heating element. In one embodiment, each heating element section is responsive to an input power frequency, and the output temperature of the substrate support surface is determined by adjusting two or more input power frequencies of the power supply.
In yet another aspect, a method is provided for controlling the temperature of a surface of a substrate disposed on a surface of a substrate support assembly. The method includes heating a surface of a substrate disposed in a processing chamber by heating a substrate support surface of a substrate support assembly on which the substrate is disposed. The substrate support assembly includes a heating element having two or more heating element sections. These heating element sections are connected together as one electrical loop, and each heating element section responds differently to the input power of the power source connected to the heating element. The method further includes determining a response power input resonance frequency in these two or more heating element sections of the heating element and providing the response power input resonance frequency to a power source connected to the heating element. In one embodiment, the method includes flowing a cooling medium that circulates through a fluid channel embedded in the substrate support assembly to further control the temperature of the substrate support surface.

  In other embodiments, the amplitude of the respective response power input resonant frequency for each heating element section is adjusted during substrate processing. In still other embodiments, by independently heating each heating element section of the heating element, a desired output temperature distribution across two or more heating zones of the substrate support surface of the substrate support assembly is achieved, each The heating element section corresponds to a respective heating zone of the two or more heating zones of the substrate support surface.

  In order that the features of the present disclosure as set forth above may be more fully understood, the invention, as outlined above, may be more specifically illustrated by reference to the embodiments, some of which are illustrated in the accompanying drawings. I will explain it. However, since the accompanying drawings show only typical embodiments of the present invention, the present invention can also include other embodiments that are equally effective within the scope thereof, and therefore the accompanying drawings are not included in the scope of the present invention. Note that this should not be considered limiting.

1 is a schematic top view of a conventional single zone substrate support assembly for illustration. FIG. It is a schematic top view of the other conventional substrate support assembly for description which is a two zone type. FIG. 2 shows an overview of an illustrative processing chamber according to an embodiment of the present invention having a substrate support assembly with a temperature adjustable multi-zone heating pedestal. FIG. 2B illustrates one embodiment of a cross-sectional view of the processing chamber of FIG. 2A showing a substrate support assembly with a temperature adjustable multi-zone heating pedestal (adjustable to create three temperature zones on the surface of the substrate support assembly) At least four exemplary heating elements are shown). FIG. 3 illustrates one embodiment of a schematic top view of a substrate support assembly with an exemplary three zone heating pedestal capable of temperature adjustment, wherein the frame is the surface of the adjustable substrate support assembly according to one embodiment of the present invention. It can be adjusted to produce three temperature zones according to the configuration. FIG. 3B illustrates one embodiment of a cross-sectional view of three exemplary heating elements embedded in the substrate support assembly of FIG. 3A and adjustable to create three temperature zones on the surface of the substrate support assembly. FIG. 6 illustrates another embodiment of a cross-sectional view of three exemplary heating elements that are embedded in a substrate support assembly of a processing chamber and are temperature adjustable to create three zones on the surface of the substrate support assembly. FIG. 6 is a schematic illustration of one embodiment of three resulting heating outputs obtained by adjusting the frequency or amplitude of the power input of three exemplary heating elements.

  To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the above figures. Without special reference, it is contemplated that elements and features of one embodiment may be advantageously incorporated into another embodiment. However, since the accompanying drawings show only exemplary embodiments of the present invention, the present invention can include other embodiments that are equally effective within the scope thereof, and therefore the accompanying drawings are not included in the scope of the present invention. Note that this should not be considered limiting.

  Embodiments of the present invention provide a method and system for controlling the temperature of the surface of a substrate disposed on a substrate support surface of a substrate support assembly. The substrate support assembly is disposed within the processing chamber or substrate processing system and generally includes a minimum number of heating elements connected to one or more power sources. The heating element and the power source are configured to control and adjust the surface temperature of the substrate support surface of the substrate support assembly to create a plurality of heating zones capable of temperature adjustment. For example, using a single heating element (e.g., a single heating element loop including a pair of power input leads / output leads) to define and control a temperature adjustable heating zone, This single heating element can be embedded in the support member of the substrate support assembly. When multiple heating elements are utilized, the number of heating zones that can be temperature adjusted exceeds the number of heating elements utilized, and therefore compared to conventional substrate supports having an equal number of heating zones Reduce the number of heating elements required.

  In one or more embodiments, the heating elements in the substrate support surface of the support member are manufactured and designed from different materials, sizes and shapes and / or have different geometries to improve substrate heating efficiency. Or it consists of a plurality of heating element sections (eg two or more heating element sections) distributed in a pattern and is embedded in the support member. These heating element sections are connected together as one single electrical loop, and these heating element sections can be heated independently (or cooled with a reduced power input) by a selected power input. , Achieving various desirable temperature profiles of the substrate support surface of the substrate support assembly, thereby creating multiple heating zones capable of temperature adjustment to heat the surface of the substrate disposed thereon. As will be described in more detail below, a method is provided for independently controlling and adjusting the output temperature of a plurality of heating element sections of a heating element of a substrate support assembly.

  The term “substrate” as used herein generally includes a wafer or other suitable glass, polymer or metal substrate. The substrate can include a surface that, when placed inside the substrate processing chamber, heats to a desired temperature during substrate processing, preferably a surface that achieves a desired temperature distribution profile across the surface of the substrate. Further, the substrate is not limited to a particular size or shape. The substrate can be a round wafer having 200 mm, 300 mm, or other diameter. The substrate can also be a polygonal, square, rectangular or curved workpiece, such as a polygonal glass substrate used in the manufacture of flat panel displays, or other non-circular workpiece.

Each substrate surface may include one or more material layers that serve as a base for subsequent processing operations. For example, the substrate can include one or more layers of conductive metals such as aluminum, copper, tungsten, or combinations thereof. The substrate can also include one or more layers of non-conductive materials such as silicon, silicon oxide, doped silicon, germanium, gallium arsenide, glass, sapphire. The substrate may also include a layer of dielectric material such as silicon dioxide, organosilicate, carbon doped silicon oxide. Furthermore, the substrate can also include other materials such as metal nitrides and metal alloys depending on the application. In one or more embodiments, the gate dielectric layer and the gate so that the substrate facilitates connection with interconnect features such as plugs, vias, contacts, lines, wires that are subsequently formed thereon. A gate structure including an electrode layer can be formed.
FIG. 2A is an overview of an example processing chamber 200 according to an embodiment of the present invention having a substrate support assembly with multi-zone heating elements suitable for heating the surface of the substrate and capable of temperature adjustment as described further below. Indicates. The processing chamber 200 generally includes a chamber body 202, a lid assembly 204, and a substrate support assembly 240 (shown in FIG. 2B).

  The chamber body 202 generally includes a slit valve opening 211 formed in the sidewall of the processing chamber 200. The slit valve opening 211 is selectively opened and closed to provide access to the interior of the chamber body 202 by a wafer handling robot (not shown). The chamber body 202 may include a chamber liner that surrounds the substrate support assembly 240. The chamber liner may be removable for service work and cleaning. The chamber liner can be made from a metal such as aluminum, a ceramic material or other material compatible with the process, and the chamber liner can be subjected to bead blasting to increase the surface roughness and / or surface area of the surface. The increase in roughness and / or surface area increases the adhesion of the material deposited on the chamber liner, thereby preventing delamination of the material that will eventually become a contaminant in the processing chamber 200. In addition, a pumping channel can be formed in the chamber liner.

The chamber body 202 may include a channel formed in the chamber body so that the heat transfer fluid flows therethrough. This heat transfer fluid can be a heating fluid or a coolant and is used to control the temperature of the chamber body 202 during substrate processing and substrate transfer. The temperature of the chamber body 202 is important to prevent unnecessary condensation of gases or byproducts on the chamber walls. Exemplary heat transfer fluids include water, ethylene glycol or mixtures thereof. An exemplary heat transfer fluid may also include nitrogen gas.
The lid assembly 204 is disposed and connected to the upper end of the chamber body 202 and the substrate support assembly 240 is disposed at least partially inside the chamber body 202 of the processing chamber 200. In some cases, a plasma source 208 is coupled to two electrodes disposed in the lid assembly 204, which are connected to a plasma volume or plasma cavity between the two electrodes in the processing chamber 200. Configured to form. To form a capacitance between these two electrodes, one electrode is grounded and the other electrode is connected to a power source such as an RF power supply. In order to electrically isolate these two electrodes, the lid assembly 140 may include an isolator ring.

  FIG. 2B shows a cross-sectional view of a processing chamber 200 having a lid assembly 204 and a substrate support assembly 240 disposed inside the chamber body 202. The processing chamber 200 includes an etching chamber, a physical vapor deposition (PVD) chamber, a chemical vapor deposition (PV) chamber that includes heating a surface of a substrate (eg, a silicon substrate) disposed within the processing chamber of the substrate processing system. It can be any type of processing chamber, including CVD) chambers, cleaning chambers, and the like. The processing chamber 200 can be any substrate processing chamber available from Applied Materials, Santa Clara, California. It should be noted that the present invention can be implemented using other processing chambers available from other manufacturing industries. It is also contemplated that the heating elements described herein may be utilized in other articles, where a single heating element has multiple heating zones that can be temperature adjusted using a single. .

  With further reference to FIG. 2B, the lid assembly 204 can generally include one or more gas inlets and a showerhead assembly (eg, the showerhead 232 is shown in FIG. 2B). Are connected to the gas inlet for flowing one or several gases through the gas inlet of the showerhead 232 near the surface of the substrate 110 disposed on the substrate support assembly 240. The process gas passes through the one or more gas inlets in fluid communication with one or more gas sources and / or other gas delivery components, such as a gas mixer, typically disposed outside the chamber body 202. 204 can be entered. The lid assembly 204 can further include one or more gas outlets 234.

In order to provide a controlled and uniformly distributed gas flow through the showerhead 232 to the surface of the substrate 110 in the processing chamber 200, the lid assembly 204 may include a distribution plate and a blocker plate. The distribution plate can include one or more embedded channels or passages that contain heaters or fluid heating to provide temperature control of the lid assembly 204. A resistance heating element (not shown) can be inserted into the channel to heat the distribution plate. A thermocouple can be connected to the distribution plate to adjust the temperature of the distribution plate. This thermocouple can be used in a feedback loop to control the current flowing through the heating element of the distribution plate.
Alternatively, the temperature of the distribution plate in the lid assembly 204 can be better controlled depending on the process requirements in the processing chamber 200 through a heat transfer medium or cooling medium if necessary through the channels of the distribution plate. Any heat transfer medium such as nitrogen, water, ethylene glycol or mixtures thereof can be used. In addition, one or more heating lamps (not shown) can be used to heat the lid assembly 204. Typically, a heating lamp is placed around the top surface of the distribution plate to heat the components of the lid assembly 204 including the distribution plate by radiation.

  To regulate the flow of gas inside the processing chamber 200 that flows from the gas source through the gas inlet and showerhead 232 located in the lid assembly 204 to the processing region on the surface of the substrate 110, the processing chamber 200 includes: A vacuum pump and throttle valve can be included. The vacuum pump is coupled to a vacuum port disposed on the chamber body 202, but may be connected to a pumping channel of the chamber liner or in fluid communication with the pumping channel of the chamber liner. In this manner, the vacuum pump can be coupled to various machine chamber components to provide an outlet for excess precursor gas or unwanted product gas or contaminants generated in the processing chamber 200. The terms “gas” and “gases” are used interchangeably unless otherwise specified, and may be one or several precursors, reactants, catalysts, carriers, purges, wash, And other fluids introduced into the chamber body 202.

  As shown in FIG. 2B, the substrate support assembly 240 of the processing chamber 200 can include a heated pedestal or susceptor that generally includes a shaft 222 and a support member 220. The shaft 222 extends through a centrally located opening formed in the bottom surface of the chamber body 202 and is generally vertically disposed within the bottom of the chamber body to support the support member 220. The support member 220 has a substrate support surface in the chamber body 202 of the processing chamber 200 for supporting the substrate 110 to be processed thereon. For example, the support member 220 can have a flat or substantially flat circular or square surface on which a substantially circular or square substrate is supported. The support member 220 can generally be constructed of an aluminum material. To reduce contamination on the back side of the substrate, the support member 220 may include a removable top plate made of some other material, such as silicon, ceramic material, and the like.

  The shaft 222 is connected to a lift mechanism (not shown) disposed outside the chamber body. This lift mechanism allows the support member 220 supported by the shaft 222 to move vertically (for example, upward and downward) between the substrate processing position in the chamber body 202 and the lower substrate transfer position. To. The substrate transfer position of the support member 220 is positioned slightly below the opening 211 of the slit valve formed on the side wall of the chamber body 202. The lift mechanism can be flexibly sealed against the chamber body 202 by a bellows that prevents vacuum leakage from the periphery of the shaft 222. Accordingly, the substrate support assembly 240 of the processing chamber 200 provides heating and / or cooling of the substrate surface without interrupting the vacuum.

  In one or more embodiments, the substrate 110 may be secured to the support member 222 using a vacuum chuck. In other embodiments, a substrate (not shown) may be secured to the support member 220 using an electrostatic chuck. The electrostatic chuck typically includes at least one dielectric material surrounding an electrode (not shown), which may be disposed on the top surface of the support member 220 or formed as an integral part of the support member 220. it can. The dielectric portion of the electrostatic chuck electrically insulates the chuck electrode from the substrate 110 and the rest of the substrate support assembly 240.

  The support member 220 can include one or more holes formed through the support member 220 to accommodate one or several lift pins. Each lift pin is constructed from a ceramic or ceramic-containing material and used for substrate handling and transport. The lift pins are movable through their corresponding holes by engaging an annular lift ring disposed within the chamber body 202. The lift ring is movable in such a manner that the upper surface of the lift pin can be disposed at a position higher than the substrate support surface of the support member 220 when the lift ring is at a higher substrate processing position. On the other hand, when the lift ring is in the lower substrate transfer position, the upper surface of the lift pin is positioned lower than the substrate support surface of the support member 220. Thus, as the lift ring moves from the lower transfer position to the upper processing position, each lift pin portion passes through its corresponding respective hole in the support member 220.

  The support assembly 220 can further include an edge ring (not shown) disposed around the support member 220. The edge ring is an annular member adapted to cover the outer periphery of the support member 220 and prevent deposition on the support member 220. The edge ring can be disposed on or adjacent to the support member 220 to form an annular purge gas channel between the outer diameter of the support member 220 and the inner diameter of the edge ring. The annular purge gas channel can be in fluid communication with a purge gas conduit formed through support member 220 and shaft 222. The purge gas conduit is in fluid communication with a purge gas supply (not shown) for supplying purge gas to the annular purge gas channel. A suitable purge gas such as nitrogen, argon, helium can be used alone or in combination. In operation, the purge gas flows through the purge gas conduit into the annular purge gas channel and flows around the edge of the substrate disposed on the support member 220. Thus, this purge gas that works in conjunction with the edge ring prevents deposition on the edge and / or backside of the substrate.

The temperature of the substrate support surface of the substrate support assembly 240 can also be controlled by circulating fluid through a fluid channel embedded in the body of the support member 220. In one or more embodiments, the fluid channel is in fluid communication with a heat transfer conduit disposed through the shaft 222 of the substrate support assembly 240. This fluid channel is located inside and around the support member 220 to provide the desired heat transfer to the substrate receiving surface of the support member 220. The fluid channel and heat transfer conduit can flow a heat transfer fluid for heating or cooling the support member 220. Any suitable heat transfer fluid can be used, such as water, nitrogen, ethylene glycol or mixtures thereof.
The support member 220 can be moved vertically within the chamber body 202 so that the distance between the support member 220 and the lid assembly 204 can be controlled. A sensor (not shown) can provide information regarding the position of the support member 220 within the processing chamber 200. In operation, the support member 220 can be raised to the immediate vicinity of the lid assembly 204 to control the temperature of the substrate being processed. As such, the substrate can be heated by radiant heating emanating from the distribution plate of the lid assembly 204 or radiant heating emanating from the heating element 212 embedded in the support member 220 of the substrate support assembly 240. Alternatively, lift pins activated and moved by a lift ring can be used to lift the substrate from the substrate support surface of the support member 220 to the immediate vicinity of the heated lid assembly 204.

  One or more embodiments of the present invention use a heating element in a substrate support assembly in which a plurality of heating element sections (eg, two or more heating element sections) are connected together as one electrical loop. I will provide a. Advantageously, the heating element sections are configured to have different geometries, patterns, shapes, sizes and materials to control the temperature of the multiple zones of the substrate support surface of the support member and thus the center of the surface of the substrate Or heated independently to provide the desired temperature profile between the various parts on the outside. These heating element sections are typically made, for example, by configuring the heating element in a spiral, or by folding the heating element to make it double (ie changing the direction in which the heating element extends, for example using 180 degree folding) In a different radial distance from the centerline of the substrate support assembly. Having multiple heating element sections located at different radial distances in the substrate support assembly that constitute a single heating element means that the single heating element is controlled by a power input source, and Provide independent control of output temperature and heating efficiency between multiple heating element sections of the heating element, thereby enabling the creation of multiple temperature control zones that are radially spaced apart .

  According to one embodiment of the present invention, a minimum of one heating element may be provided in the substrate support assembly 240 to heat the surface of the substrate 110 (eg, the heating element 212 of FIG. This minimum one heating element (shown embedded in support member 220 of support assembly 240) allows for temperature adjustments that can controllably control and achieve output temperatures in a plurality of respective heating zones. Configured to produce a plurality of heating zones (which will be discussed in detail later). Additional heating elements can be provided, but may not be necessary.

  In one embodiment, the heating element 212 is a resistive heating element made of a resistive material, eg, an internal resistive wire surrounded by a certain thickness of filler material. The support assembly 220 can further include a thermocouple (not shown) embedded in the support assembly 220 to monitor the temperature of the substrate support surface of the support member 220. For example, a signal from a thermocouple may be used in a feedback loop to control the current, power input level and frequency applied to the heating element 212 and / or to circulate through a fluid channel embedded in the support member 220 or By controlling the flow rate of the coolant or the cooling medium, the output temperature of the substrate support surface of the support member 220 can be adjusted.

In one example, the heating element 212 may be connected to the power input line 226A and the power outline line 226B of the power source 214 to heat the substrate 110 disposed on the substrate surface of the support member 220 of the substrate support assembly 240. The power input line 226A and the power outline line 226B are generally disposed within the shaft 222. Advantageously, only one single power source is required when one single heating element is used, thus reducing the software control and hardware load controlling multiple power sources. In addition, a minimum of two power lines for a single heating element are housed within the shaft 222, and many power lines are shafted as found in prior art substrate supports that use multiple heating elements. There is no need to house it inside.
The heating element 212 generally converts electricity into heat by a Joule heating process. A resistance is added to the current passing through the heating element 212 so that the heating element 212 can be heated. The heating element 212 may include a wire, ribbon, or strip center that includes, but is not limited to, nickel, chromium, iron, aluminum, copper, molybdenum, platinum, silicon carbide, and the like. Resistive materials including metal alloys, these nitride materials, these silicide materials, and combinations thereof can be included. The resistive material can be an alloy of different metallic materials, and the resistive material can be doped with a metal dopant or other dopant material. The resistance heating wire, ribbon or strip can have a straight shape or a coiled shape. The filler material can be any ceramic or oxide material that provides insulation and prevents leakage.

  For example, resistance heating wires or ribbons can be made from Nichrome 80/20 (80% nickel, 20% chromium) material. Nichrome 80/20 is an ideal material because it has a relatively high resistance and forms an adhesion layer of chromium oxide when first heated. The material under this chromium oxide layer does not oxidize and protects the wire from disconnection or burnout.

In addition, Kanthal (FeCrAl) and Cupronickel (CuNi) and their alloys are also excellent materials for low temperature heating. Molybdenum disilicide (MoSi _2, molybdenum silicide or MOSI ₂₎ intermetallic compounds are silicides of molybdenum, a refractory ceramic which may be used in the heating element. Molybdenum disilicide has a medium density, a melting point of 2030 degrees Celsius, and is conductive. Molybdenum disilicide forms a silicon dioxide passivation layer at high temperatures, which prevents further oxidation of the molybdenum disilicide.

As another example, molybdenum disilicide is doped with aluminum (Al) and aluminum doped molybdenum disilicide or Mo (SiAl) ₂ , which is also a refractory ceramic that can also be used in a heating element. Can be formed. Aluminum doped molybdenum disilicide forms an alumina (Al ₂ O ₃ ) passivation layer at high temperatures, which corrodes or further oxidizes the aluminum doped molybdenum disilicide. Is prevented. In a reducing atmosphere, the melting temperature of aluminum-doped molybdenum disilicide is 300 degrees Celsius higher than the melting temperature of molybdenum disilicide (MoSi ₂ ).

Other materials suitable for use as heating element 212 include screen-printed metal (which can be insulated with a ceramic material), etched metal foil (subtractive photo-etching process). Produced by forming a complex resistance pattern on a continuous sheet of metal foil), and ceramic encapsulated inside a tube made from stainless steel or brass as a straight or curved rod that spans the area to be heated Tubular coil nickel chrome wire (often known by the trademark “Calrod”) in an insulating bond (MgO or alumina powder) is included. In addition, a positive thermal (PTC) ceramic material having a thermal coefficient of positive resistance can be used (compared to most ceramics having a negative thermal coefficient). This type of ceramic material (eg barium titanate and lead titanate composites) has a highly non-linear thermal response and is extremely resistant at temperatures above the composition-dependent threshold temperature, which makes this material Functions as its own thermostat so that when connected to current (when on), the current flows when the temperature of the material is low (cold) and no current flows when the material is hot. In addition, these PTC ceramic materials can be thin films and / or various shapes.
In one or more embodiments, the heating element 212 is configured to have multiple portions (eg, at least four heating element sections 212A, 212B, 212C, 212D are shown in FIG. 2B), and thus One single heating element has the ability to provide multiple temperature zones on the substrate support surface of the support member 220 of the substrate support assembly 240. In one example, heating element sections 212A, 212B, 212C, 212D of heating element 212 have at least four heating zones “A”, “B”, “C”, and “D” that span the entire substrate support surface of support member 220. Configured to provide. Each heating element section can be configured to provide heating in each heating zone of the substrate support surface of the support member 220. In one embodiment, the heating elements 212 are such that these four heating zones “A”, “B”, “C” and “D” are defined at different radial distances from the centerline of the substrate support. The heating element sections 212A, 212B, 212C, 212D are arranged at different radial distances. In one embodiment, the heating element sections 212A, 212B, 212C, 212D are configured to be concentric such that the four heating zones “A”, “B”, “C”, and “D” are concentric. .

  In one or more embodiments, several variables, among others, for example, the size, shape and pattern (or distribution density) of the resistive heating material or filler material of each heating element section of the heating element 212, of the support member 220, The output temperature of each heating zone is controlled by the size, shape, pattern and geometry (or density) of each heating zone distributed on the substrate support surface, the input power frequency of the power supply 214, and the amplitude of each power frequency, Can be determined. As a result, a plurality of zones “A”, “B”, “C”, “D”,. . . The output temperature at etc. is independently controlled by adjusting these variables (eg, within a plurality of respective heating element sections 212A, 212B, 212C, 212D,..., Etc. of a single heating element 212). And can be determined to achieve a desired temperature distribution on the substrate support surface of the support member 220 and thus the desired surface temperature distribution profile resulting from the surface of the substrate.

  FIG. 3A shows an example of a support member 220 of a substrate support assembly 240 with a temperature adjustable three-zone heating pedestal, where the small frame shows that the substrate support surface of the support member 220 has three concentric temperature heating zones “A”. ”,“ B ”, and“ C ”. The shape of the heating zones “A”, “B”, “C” can be concentric circles or other suitable shapes.

  In FIG. 3A, the heating element 212 embedded in the support member 220 is a substrate support member, for example, by folding the heating element 212 into a double, orienting the heating element 212 in a spiral, or by other configurations. It includes at least three heating element sections 212A, 212B and 212C located at different radial distances from the 220 centerline. In one embodiment, the heating element sections 212A, 212B and 212C are made of the same resistive heating material and are configured to have different geometries or patterns. For example, to compensate for heat loss at the edge of support member 220, heating element section 212C or a heating element section located near the outer edge of support member 220 may be geometrically higher than heating element section 212A. It can be configured as a density pattern. In other embodiments, heating element section 212C or support member 220 may be used to increase the heating efficiency in heating zone “C” over the heating efficiency in the other heating zones and compensate for heat loss at the edges of support member 220. The heating element section disposed near the outer edge may be configured in a coiled shape or other shape that is not a loosely wound coil, a tubular wire or a ribbon shape.

  In one example, each heating element section 212A, 212B, 212C is heated (eg, connected to a power source for heating) to produce different heating power efficiencies and a desired temperature distribution on the substrate support surface of the support member 220. ) Forming resistive wires, coils, ribbons (especially) having different thicknesses so that each heating element section can be tuned and controlled to have its own response power input resonant frequency or phase May be composed of the same resistive material.

In other examples, each heating element section 212A, 212B, 212C is heated (eg, to a power source for heating) to produce different heating power efficiencies and a desired temperature distribution on the substrate support surface of the support member 220. Each heating element section (when connected) may be composed of the same resistive material with a different filling material or concentration such that it has its own resonant frequency or phase.
In other embodiments, each heating element section 212A, 212B, 212C is heated (eg, powered to heat) to produce different heating power efficiencies and a desired temperature distribution on the substrate support surface of the support member 220. Each heating element section may be composed of a different resistive material or a different filling material so that each heating element section has its own response resonant frequency or phase.
Thus, a method of heating a substrate support surface of a substrate support assembly includes determining a response power input resonance frequency in two or more heating element sections of the heating element and connecting the response power input resonance frequency to the heating element. Including feeding to other power sources.

  FIG. 3B shows an example of three heating element sections 212A, 212B, 212C that form the heating element 212 embedded in the substrate support assembly 240 of FIG. 2B. In one or more embodiments, the heating element sections 212A, 212B, 212C can each include an outer portion 216 and a central portion 218A, 218B, 218C, where the central portions 218A, 218B, 218C are the heating element section. 212A, 212B, 212C can be controlled, tuned or tuned to produce three temperature heating zones “A”, “B”, “C” on the surface of the substrate support assembly 240 in different ways. Or are formed to different thicknesses. The outer portion 216 can be made of the same or different filler material. The central portions 218A, 218B, 218B can be resistance wires, coils, ribbons, among others.

  FIG. 3C shows another example of heating element sections 212A, 212B, 212C embedded in the substrate support surface of support member 220 in the processing chamber. In this embodiment, the heating element sections 212A, 212B, 212C can each include a central portion 218 and outer portions 216A, 216B, 216C, and the outer portions 216A, 216B, 216C can include heating element sections 212A, 212B, Formed from different filler materials in such a way that 212C can be controlled, adjusted or tuned to create three temperature heating zones "A", "B", "C" on the surface of the substrate support assembly 240, or Formed in different thicknesses. The central portion 218 can be made of the same or different resistance wire, coil or ribbon material. The outer portions 216A, 216B, 216C are independently controlled, tuned or adjusted to produce three heating efficiencies in the temperature heating zones “A”, “B”, “C” of the substrate support surface of the support member 220. Can do.

  Referring again to FIG. 2B, a heating element 212 that includes two or more multiple heating element sections can be connected to a power source 214, which provides the power input of the power source 214 to the plurality of respective heating element sections. Connected to a controller containing embedded software for tuning and tuning. The power supply 214 can be controlled directly or indirectly by the system controller 206 or a separate controller connected to the system controller 206, which is generally used for the purpose of regulating the operation of the processing chamber 200. Accordingly, the system controller 206 can be configured during substrate heating to achieve heating of the support surface of the substrate support assembly. The system controller 206 can be configured to determine a response power input resonance frequency in two or more heating element sections of the heating element and provide the response power input resonance frequency to a power source connected to the heating element.

  A system controller 206 can be coupled to various components of the processing chamber 200 to control substrate processing operations of the processing chamber 200. Although schematically shown as being coupled to the processing chamber 200, the system controller 206 is configured to control the power supply 214, the substrate support assembly 240, the processing to control processes performed within the processing chamber 200. Various sensors and thermocouples in the chamber 200, a gas supply device (not shown) coupled to a gas inlet near the showerhead 232, one or more gas outlets 234, a vacuum pump and / or a throttle valve (not shown). )) Or the like. The system controller 206 can be a computer processor or sub-processor of any form of general-purpose computer processor and sub-processor that can be used in an industrial environment that controls various processing chambers and chamber components. The system controller 206 can directly control the processing chamber 200 or other computer or controller associated with a particular support system component can be controlled (not shown).

  As shown in FIG. 2B, the system controller 206 generally comprises a central processing unit (CPU) 308, a storage device 312, and support circuitry 310 for the CPU 308. The storage device 312 (eg, computer readable medium) of the CPU 308 is readily available, such as random access memory (RAM), read only memory (ROM), floppy disk, hard disk, flash or any other form of local or remote digital storage. There may be one or more of the possible storage devices. Coupled to the CPU 308 is a support circuit 310 that supports the CPU 308 in a conventional manner. These support circuits 310 include a cache, a power supply device, a clock circuit, an input / output circuit, a subsystem, and the like.

  The inventive method described herein can be stored in the storage device 312 as a software routine 314 that executes or calls the software routine 314 to control the operation of the processing chamber 200. Adjusting the power input (frequency, amplitude, power level, etc.) of the power supply 214 to control the heating efficiency and temperature distribution of the substrate support surface of the substrate support assembly 240, thereby improving the heating efficiency and processing The desired temperature distribution across the surface of the substrate disposed in the chamber 200 can be turned into a special purpose controller that achieves according to the scheme described herein. This software routine can also be stored and / or executed by a second CPU (not shown) located away from the hardware controlled by the CPU 308.

The storage device 312 can include instructions that allow the tuning / temperature adjustment process described herein to be performed on the processing chamber 200. The computer program includes, for example, heating and cooling sequencing and timing, wafer cooling, various gas and gas mixture inflows and outflows, chamber pressure, RF power levels, substrate support assembly shaft and support member positioning, Lift pin positioning, slit valve opening and closing, and other variables and parameters can be commanded.
FIG. 4 illustrates two of the heating elements (eg, heating element 212) to provide a desired temperature distribution between heating zones “A”, “B”, “C”, etc. of the substrate support surface of the substrate support assembly. An example of tuning the heating power of the above heating element section or any other number of multiple heating element sections (eg, heating element sections 212A, 212B, 212C) is shown. In one example, a modulator connected to the power supply and system controller 206 can be used to adjust the power supply 214, such as adjusting the frequency of the power input applied to the heating element sections 212A, 212B, 212C, resulting in Three different heating power levels are obtained.

In another example, the result is by adjusting the amplitude of each particular frequency f (A), f (B), f (C) that each heating element section 212A, 212B, 212C can respond to. Three different heating power levels are obtained (eg, heating element section 212A is responsive to power input at frequency f (A), heating element section 212B is responsive to power input at frequency f (B), and heating element section 212C is Responds to power input at frequency f (C)). By adjusting the amplitude of each frequency, the temperature of each heating zone “A”, “B”, “C” (shown in FIG. 2B) can be adjusted independently. Additional methods of adjusting the peak amplitude of each frequency, and thus changing the temperature of the corresponding heating zone, can be used to achieve the desired temperature distribution profile.
Thus, by independently adjusting the temperature of each heating zone of the substrate support surface of the substrate support assembly, the temperature distribution profile of the surface of the substrate disposed on the substrate support assembly is optimized and such temperature distribution profile Can be obtained. As discussed above, it removes excess heat generated by the heating element or heating element section (when the power supply connected to the heating element is turned on with a power input greater than 0.01% This) of the substrate support assembly to maintain control of the heating elements and simultaneously manipulate the temperature of each heating element section (corresponding to each heating zone) to achieve the desired temperature distribution on the surface of the substrate. A cooling channel or cooling fluid may be incorporated into the heating mechanism.

  Accordingly, the present invention is a simple and clean method for efficiently and independently controlling the temperature of a substrate disposed inside a processing chamber, which is unnecessary and bulky such as multiple power lines, cables and power leads. A method for eliminating parts is provided. In a heating system that includes at least one heating element incorporated within a substrate support assembly to provide substrate heating in a plurality (N) of heating zones, approximately N-1 sets of cables and heating element leads, N -It is estimated that the cost of designing and installing a set of power supply units will be reduced. In addition, when fewer chamber parts are used, potential chamber downtime and default due to malfunction of these multiple sets of cables, leads and power supply units is greatly reduced.

  The processing chamber 200 can be coupled to a multi-chamber substrate processing system (eg, a cluster substrate processing tool) that can be adapted to perform various processes within a plurality of processing chambers. Each processing chamber within the substrate processing system is capable of chemical vapor deposition (CVD), cyclic layer deposition (CLD), atomic layer deposition (ALD), physical vapor deposition (PVD), etching. Configured to perform at least one substrate processing operation, such as degassing, dry etching, pre-cleaning, orientation and other substrate processes. The substrate processing system can further include one or more load lock chambers for transferring the substrate into and out of the substrate processing system.

  A transfer robot can transfer the substrate between the load lock chamber and / or the first set of one or more processing chambers and between the other chambers. The transfer robot can also transfer substrates to / from one or more transfer chambers. A transfer chamber can be used to maintain ultra-high vacuum conditions, and at the same time, it can be possible to transfer a substrate within a substrate processing system. Another transfer robot may transfer the substrate between the transfer chamber and / or the second set of one or more processing chambers.

  While the above description is directed to embodiments of the invention, other additional embodiments of the invention may be devised without departing from the basic scope of the invention. The scope of the invention is determined by the following claims.

Claims (20)

In the substrate processing chamber,
A support member comprising a substrate support surface;
A heating element comprising two or more heating element sections, said heating element sections being connected together as one electrical loop with a pair of power input REIT wires and power output leads , each heating element A substrate support assembly, wherein the section comprises a heating element that independently responds differently to the input power of a power source connected to the heating element.   The heating element is provided to heat two or more heating zones of the substrate support surface, and each heating element section is independent to heat a respective heating zone of the substrate support surface of the support member. The substrate support assembly of claim 1 configured as described above.   The substrate support assembly of claim 1, wherein each heating element section is responsive to an input power frequency, and the temperature of the substrate support surface is determined by adjusting two or more input power frequencies of the power source.   The temperature of each heating element section is determined by the amplitude of the input power frequency of the power supply, and the temperature of the substrate support surface is controlled by adjusting the amplitude of the power frequency. Substrate support assembly.   Each heating element section is selected from the group consisting of nickel, chromium, iron, aluminum, copper, molybdenum, platinum, silicon carbide, their metal alloys, their nitride materials, their silicide materials and combinations thereof The substrate support assembly of claim 1, comprising a resistive heating material.   The substrate support assembly of claim 1, wherein each heating element section comprises a resistive heating material having a shape selected from the group consisting of a wire, foil or ribbon.   The substrate support assembly of claim 1, wherein each heating element section includes filler materials of different sizes and shapes.   The two or more heating element sections are formed differently according to the variables of the respective heating element section so that when the power supply connected to the heating element is on, in the two or more heating element sections The substrate support according to claim 1, wherein different temperatures are achieved, and the variables are selected from the group consisting of resistance heating material size, shape, pattern, distribution density, filling material size, shape, pattern, distribution density. assembly. A substrate processing chamber,
A substrate support assembly disposed inside the substrate processing chamber, the substrate support assembly comprising:
A support member comprising a substrate support surface;
A heating element comprising two or more heating element sections, said heating element sections being connected together as one electrical loop with a pair of power input REIT wires and power output leads , each heating element A substrate processing chamber, wherein the section comprises a heating element that independently responds differently to input power of a power source connected to the heating element.   The heating element is provided for heating two or more heating zones of the substrate support surface, each heating element section of the heating element heating a respective heating zone of the substrate support surface of the support member. The substrate processing chamber of claim 9, wherein the substrate processing chamber is configured independently.   The substrate processing chamber of claim 9 selected from the group consisting of an etching chamber, a cleaning chamber, a CVD chamber, a PVD chamber, an ALD chamber, and combinations thereof.   The substrate processing chamber of claim 9, wherein each heating element section is responsive to an input power frequency, and the temperature of the substrate support surface is determined by adjusting two or more input power frequencies of the power source.   The temperature of each heating element section is determined by the amplitude of the input power frequency of the power supply, and the temperature of the substrate support surface is controlled by adjusting the amplitude of the power frequency. Substrate processing chamber.   Each heating element section consists of a filling material and nickel, chromium, iron, aluminum, copper, molybdenum, platinum, silicon carbide, their metal alloys, their nitride materials, their silicide materials and combinations thereof The substrate processing chamber of claim 9 comprising a resistance heating material selected from the group.   The substrate processing chamber of claim 9, wherein each heating element section comprises a resistive heating material having a shape selected from the group consisting of a wire, foil or ribbon.   The two or more heating element sections are formed differently according to the variables of the respective heating element section so that when the power supply connected to the heating element is on, in the two or more heating element sections 10. Substrate processing according to claim 9, wherein different temperatures are achieved and the variables are selected from the group consisting of resistance heating material size, shape, pattern, distribution density, filling material size, shape, pattern, distribution density. Chamber. A method for heating a surface of a substrate in a processing chamber, comprising:
Heating a substrate support surface of a substrate support assembly on which the substrate is disposed, the substrate support assembly comprising a heating element including two or more heating element sections, the heating element section comprising a pair of heating element sections The method is connected together as one electrical loop with a power input lead and a power output lead , each heating element section responding differently to the input power of a power source connected to the heating element, the method Furthermore,
Determining a response power input resonance frequency in the two or more heating element sections of the heating element, and providing the response power input resonance frequency to the power source connected to the heating element. The method of claim 17, further comprising adjusting an amplitude of each response power input resonance frequency for each heating element section. Further comprising independently heating each heating element section of the heating element, each heating element section corresponding to a respective heating zone of two or more heating zones of the substrate support surface, the method comprising: ,
The method of claim 17, further comprising: providing a desired temperature distribution across the two or more heating zones of the substrate support surface of the substrate support assembly. The method of claim 17, further comprising: flowing a cooling medium that circulates through a fluid channel embedded in the substrate support assembly; and adjusting a temperature of the substrate support surface of the substrate support assembly.

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